Drafting instrument



Nov. 26, 1963 F. J. RODGERS DRAFTING INSTRUMENT Filed June 26, 1959 FIGZ FIG-l INVENTOR.

FRANK J. RODGERS United States Patent 3,111,765 DRAFTING- llNdTRUMENT Frank J. Rodgers, 190 Commonwealth St, Franklin Square, N.Y. Filed June 26, 1959, Ser. No. 823,172 2 Claims. (Cl. 33-108) This invention relates to drafting instruments and more particularly to drafting guides and templates such as triangles, geometric shapes, French curves and combinations thereof, connected together in predetermined manner.

The present invention provides a first guide or template such as a triangle and a second guide or template such as a triangle, geometric shape, French curve and combinations thereof, movably mounted with respect to the first triangle by means of a parallelogram connection. The second smaller triangle preferably has a small knob thereon so that it may be easily moved with respect to the first larger triangle. Therefore, the second triangle may be moved in parallel relation by the simple radial motion of the fingers of the draftsman or person skilled in the art while his wrist rests on the first triangle. With the present apparatus this simple finger motion eliminates the necessity for moving both the straightedge and conventional triangle in sequence familiar to those skilled in the art of drafting equipment for drawing adjoining, intersecting, parallel, geometric forms, center lines, or crosshatching. Therefore, this detail work can be performed much more quickly and accurately with the present device.

If desired, the smaller triangle may be made with an aperture in the center area to provide an angular or shaped working surface in relation to the outside and notched to provide uniformly spaced means for laying off short lines for crosshatching smaller areas. The short lines or marks then can be extended to the desired length by aligning the corresponding slot to the lines or marks by radial movement of the smaller triangle and executing the lines to the desired lengths or spacings.

in another embodiment of the invention the small triangle may be mounted without any mechanical connection to the larger triangle, but accurate indexing means are provided in that both the larger and smaller triangle have notched teeth along their longer edge so that the smaller triangle may be accurately spaced along the larger triangle for the purpose of drawing parallel lines such as crosshatching. The smaller triangle may also be slotted at predetermined angles if desired for special purposes.

Another embodiment of the invention is also illustrated wherein the larger triangle has a pivotally mounted blade together with a thumb screw connector so that various angles, intersecting lines, and geometric forms may be laid off from the larger triangle for the purpose of, for instance, perspective drawings.

Accordingly, a principal object of the invention is to provide new and improved drafting means.

Another object of the invention is to provide new and improved drafting means comprising a first triangle and a second smaller triangle movably mounted on said first triangle with parallelogram connection means whereby the small triangle may be moved in parallel relation to the larger triangle for the purpose of making center line crosses and parallel lines, for instance, crosshatching, with a minimum of movement on the part of the operator.

Another object of the invention is to provide first and second triangles having notched edges whereby one triangle may be accurately spaced along the other triangle.

Another object of the invention is to provide triangles which are apertured and notched with uniformly spaced teeth along the interior apertures.

3,111,765 Patented Nov. 26, 1963 These and other objects of the invention will be apparent from the following specification and drawings, in which:

FIGURE 1 is a plan view of an embodiment of the invention.

FIGURE 2 is a sectional view taken along the line 2-2 of FIGURE 1.

FIGURE 3 is a plan view of another embodiment of the invention.

FIGURE 4 is an enlarged sectional view taken along the line 44 of FIGURE 3, and

FIGURE 5 is a plan view of another embodiment of the invention.

Referring to the figures, the invention generally com prises a first triangle guide l which may be a conventional adjustable plastic triangle or which may be of the type shown which has a pivotally mounted blade 2 which is mounted on the triangle 1 by means of the pivotal connection 3. The blade is adapted to be connected to the triangle at any particular angle by means of the slotted extension member 4 which is fixedly connected to the blade 2 and which has a curved slot '5, which may be calibrated in degrees of angle, therein through which the thumb screw connector 6 mounted on triangle .1 eX- tends for the purpose of fastening the blade 2 at any desired angle to the edges of the triangle 1.

A smaller triangle guide ill is movably mounted with respect to the larger triangle 1 by means of the pivotally mounted parallelogram type connecting links 11 and 12. The purpose of this type mounting of the smaller triangle is to provide means for laying off a series of parallel lines and also lines perpendicular to those parallel lines or for the purpose of making crosses such as 13 or corners 14 and 15. The smaller triangle may also be slotted in predetermined angular relation to its edges, for instance, the slots to and 17 which are arranged to lay off lines at 45 to the edges of the triangle.

FIGURE 2 shows an enlarged sectional detail view i-llustrating one method of connecting the smaller triangle it to the larger triangle. This section is taken along line 22 of FIGURE 1 through the connecting link 11 which is connected to the larger triangle or in this case the blade 2 by means of a countersunk rivet 26 upon which is mounted the link 11, the rivet extending loosely through a hole in the link and the link being fastened down by means of a washer 21 and a screw type or other connector 22 fastened to the rivet 2d. The smaller triangle 10 may be directly connected to the link 11 in a similar manner or it may be connected as illustrated by an additional channel member .23 which is freely, rotatably connected by rivet 29 to the other end of the link 11. The channel member 23 has a U-shaped cross section into which the extending edge 24 of the smaller triangle Jill" is inserted. The smaller triangle 10 is adjustably secured to the channel by means of the thumb screw 25, FIGURE 1. The edge of the smaller triangle and the abutting inside edge of the channel member 26 provide quick alignment of the smaller triangle ill to the parallel linkage and securing thereof with set screw 25 for quick removal of the smaller triangle It) for use in the variation shown in FIGURES 3 and 4.

FIGURES 3 and 4 show a simplified variation of the invention which eliminates the parallelogram connections but provides for uniform spacing of the smaller triangle 3'9 with respect to the larger triangle 31 by means of the teeth 32 cut in both the larger and smaller triangles.

The protruding toothed edge 33 of the smaller triangle preferably rides over an extending lip 34 of the larger triangle as shown in the detail view of FIGURE 4 and is indexed along the mating teeth 32.

FIGURE 5 shows another modification of the invention wherein the smaller triangle 35 has apertures '56 and 37 each of which has a series of equally spaced notches 33 and 39 of any manufactured size. The triangle 35 has inside ruling edges 49 and 4-1 and outside ruling edges 42 and The notched edges may be used for marking off equally and regularly spaced intervals, for instance, for locating crosshatchi-ng or similar purposes, for producing directly therewith lines equally spaced and also combining the marked off intervals with conventional use of the adjacent inside ruling edges 49 and 41 or outside ruling edges 42, 43, :4, as desired for execution of line Work. Various types of line work may be produced, such as intersecting, parallel, and geometric form lines or combinations thereor" dependin upon the requirements.

Therefore, the resent invention provides a new and improved drafting means which greatly simplifies the drawing of regularly soaced lines and other sgecial lines such as center crosses, adjoining, intersecting lines, geometric shapes, depending neon result desired by the person skilled in the art. With the present apparatus these lines may be made by moving the smaller triangle with the fingers. Otherwise these lines would have to he (made by moving a series of difierent triangles along a T-square or similar pm'alle-l or straightedge or device together with movement of the T-square or similar parallel or straightedge or device itself and re eated movements to position ruling edges for the execution of the desired line work, also at times utilizing a ruled scale and combination thereof to produce a desired line work. Such movements involve moving in position and at times utilizing two hands, many various instruments familiar in the art for execution of a desired line work and make it difilcult or 4 impossible to accurately space lines such as cross hatching.

1 claim:

1. A drafting instrument corn rising a first triangle shaped guide, a second triangle shaped guide considerably smaller than said first guide, and parallelogram means to rnovably mount said second guide in a central location on said first lguide, said second guide having guide apertures in predetermined angular relation to said second triangle shaped guide.

2. Drafting means comprising a first triangle guide, a blade member pivotally mounted on said first guide, adjustable angle neans connecting said blade member and said first guide, a parallelogram linkage connected to said blade member, and a second triangle guide adjustably mounted on said blade member by means of said parallelogram linkage.

References Cited in the file of 'this patent 

2. DRAFTING MEANS COMPRISING A FIRST TRIANGLE GUIDE, A BLADE MEMBER PIVOTALLY MOUNTED ON SAID FIRST GUIDE, ADJUSTABLE ANGLE MEANS CONNECTING SAID BLADE MEMBER AND SAID FIRST GUIDE, A PARALLELOGRAM LINKAGE CONNECTED TO SAID BLADE MEMBER, AND A SECOND TRIANGLE GUIDE ADJUSTABLY MOUNTED ON SAID BLADE MEMBER BY MEANS OF SAID PARALLELOGRAM LINKAGE. 